RECENT HIGHLY PATHOGENIC NEWCASTLE DISEASE IN PAKISTAN Dr. Muhammad Mustafa Kamal 05/11/2012

LESSONS LEARNT FROM RECENT NEWCASTLE DISEASE OUTBREAK IN PAKISTAN

RECENT OUTBREAKS The Problem Started in November 2011 Losses due to ND in broiler ranged from 5% to 80% Most outbreaks were around Lahore, Karachi and Islamabad ND was also recorded in Parent Stock Incidence of disease in Parent Stock was less ( Bio-security / Better Vaccination ) In younger Parent Stocks, in case of disease mortality was high

STAKE HOLDERS INVOLVED Farmers / PPA Government ( PRI,NARC and VRI ) Educational Institutions ( UVAS and AUF )

ROLE OF PPA Education of farmers was started on standard disease prevention principles All the research and field scientists were invited to give their inputs on the issue Research organisations were asked to work on the prevailing virus and vaccine efficiency

ROLE OF GOVERNMENT AND EDUCATIONAL INSTITUTIONS

STUDIES AT VRI Initial work at VRI indicated that Mukteswar vaccine was effective in controlling the disease Homologus vaccine was prepared, which was found effective in lab conditions.

STUDIES AT PRI Homologus killed vaccine at 10 th day along with live lasota vaccine gave best protection 92.85% Homologus killed vaccine at day 1 did not prove effective Mukteswar killed vaccine at day 10 th also gave significant protection 83.72%

STUDIES AT N.A.R.C On Phylogenetic basis the new strain belongs to genotype VII, close to Malaysia, Taiwan and Indonesian isolates. Multiple sub-genotypes were identified ( VIIa, VIIc, VIId ) No major mutation at 5 known neutralizing epitopes of F-Protein and no shift in 3 major amino-acids in Receptor binding sites (RBS) of HN protein. So current vaccine may still work if used judicially

STUDIES AT UVAS Homologus vaccine was effective and gave protection

STUDIES AT DIFFERENT COMMERCIAL FARMS

Vaccine schedule AgeVaccineRout 1ND+IB liveND killedSpray + SC 8Gumborodw 10ND mukteswarED 13IB (H120)dw 15Gumborodw 19ND Lasotadw Titers AgeND Killed ND at day 1 did not give protectectio n titers at any age ND started at day 28 34% depletion Trial 1 Conclusion: Killed Vaccine at Day 1 could not give protection, In presence of M Abs High Maternal Antibodies interfere with early vaccination

Vaccination schedule AgeVaccineRout 1ND+IBND killedSpray +SC 9ND lasotaND MukteswarDW+ED 12IB (H120)DW 16GumboroDW 18ND lasotaDW 29ND lasotaDW Titers AgeNDH Trial 2 ND started on day 31 st Flock marketed at 35 th day with 4% depletion with ND Wt 1633 Fcr 1.86 Conclusion : Compromised protection Skip 29 th day vaccine in next flocks Avoid too many vaccines

Trial 3 25 th day Protecte d titers 6.29 Conclusion : Spray vaccine at Day 20 rapidly increased titers after only 5 days Vaccine schedule AgeVaccineRout 1ND livespray 1IBD Immune ComplexSC 4IB H120DW 10 ND killed ND Mukteswar ND Lasota SC ED dw 20ND LiveSpray Titers AgeNDH Spray vaccination method is more effective than drinking water or eye drop vaccination methods in case of live ND vaccines

Trial 4 Spray vaccine at Day 15 Conclusion : Protected titers achieved at day 25 Vaccine schedule AgeVaccineRoute 1ND(clone)livespray 1IBD Immune complexSC 4IB (H120)DW 7ND killedSC 7ND MukteswarED 15ND clonespray Titers AgeNDH Spray vaccination method is more effective than drinking water or eye drop vaccination methods in case of live ND vaccines

Vaccine schedule AgeVaccineRout 1ND+IB livespray 1 IBD Immune complexSC 7ND+H9 killedSC 15ND clonespray Titers AgeNDH As in this case M Abs against Nd are very high Killed Vaccine injected at day 7 instead of day 1, Live vaccine sprayed at day 15 Protected titres achieved at day 20 Conclusion: In presence of high Maternal Abs Killed ND should be delayed Trial 5 Delayed first killed vaccine was useful

CONCLUSIONS DRAWN Killed vaccine can be used incase of high challenge Delay the first killed vaccine in the presence of high maternal antibodies Reduce number of vaccines Spray method is more effective for live vaccine application Standard vaccines are effective so homologus vaccines may not be required

LESSONS FOR ALL STAKE HOLDERS

FARMERS/ PPA/ FIELD VETERINARIANS Proper Bio-security principles should be implemented Distance between the farms should be observed Proper hygiene and disinfection should be exercised Field Veterinarians should design proper vaccine schedules Proper effective mode of application like spray vaccine is more effective than drinking water Timing of vaccine application is important Routine monitoring of vaccine responses.

GOVERNMENT/ EDUCATIONAL INSTITUTES Initial response of institutional heads was very encouraging as they offered their services voluntarily Government should introduce the LAW of PROXIMITY to save future development of poultry Research Organisations should be provided with funds to do research at all times on prevailing pathogens Emphasis should be on study at molecular level, genetic sequencing of viruses Quality of research needs to be improved